Amélie director Jean-Pierre Jeunet has been off the radar for a good five years; he's spent most of the time since 2004's A Very Long Engagement working on an adaptation of The Life of Pi that is yet to see the light of day. Instead, he has turned out an engaging, good-natured caper movie that, while not exactly thrown together, doesn't quite burst out of the screen in the way his Audrey Tautou movies did. Certainly Jeunet shoehorns in a full quota of elaborate ­design, ­physical hi-jinks and camera gags, but the effect is just a little low-res. ­Perhaps it's partly down to bland Dany Boon in the lead: his comic gifts, whatever they are, don't seem to translate. Boon plays a mild-mannered video store clerk called Bazil who takes a stray bullet to the head; the doctors can't remove it and he ends up living rough with a band of underground weirdos (the Micmacs of the title). Aided by the Micmacs – one ­invents Heath Robinson-type ­contraptions, another is a contortionist, another a human cannonball – Bazil cooks up a convoluted scheme to take revenge on the arms manufacturers who maimed him (and killed his father). ­Jeunet has a lot of fun; but his film is straining to ­generate charm that doesn't quite ­materialise.